And so the discussion goes back and forth
.Brent you should try some Nosler brass. Measure the headspace with an appropriate gauge before and after and see if it grows after firing .Actually it would be prudent to measure 3 datums across the shoulder.
If there is indeed a 14thou difference then a properly fire formed case should end up at least .014 longer than a new case. In my case with a 280ai cooper it doesn't grow at all.

Now to muddy the water in the below article click on the case and you see the case that was in Sierra manual and Nosler before Nosler decide to do the SAAMI Spec 280AI. On page two of the article they mention loading data from those manuals.

Now to muddy the water in the below article click on the case and you see the case that was in Sierra manual and Nosler before Nosler decide to do the SAAMI Spec 280AI. On page two of the article they mention loading data from those manuals.

Interesting and the base to neck/shoulder junction reads 2.175 which is only .001 off the above diagram of the supposedly new saami version. Tis only a sketch though.

There is no way you can blow 280 case out to the SAAMI spec 280AI and keep the same case length @ 2.540".

My big question how close was the older 280AI prior to SAAMI spec to what was published in Sierra/Nosler manuals?

Why would Sierra and Nosler publish case spec and loading data for a 280AI prior to SAAMI spec 280AI if that wasn't the case being used at the time, they both had reamers. If you look at Ackley book vol I for the 280 Improved(Ackley) all the loading data came from RCBS page 395/396.